This application is for renewal of the core grant which has provided essential support for the research program of the Sloan-Kettering Institute for Cancer Research. This is a program of cancer research, many aspects of which are closely linked with the treatment activities of our sister organization, Memorial Hospital. The core grant has provided partial support of salaries of approximately 11% of the professional staff including most of the Institute's scientific leadership, and has underwritten supporting resources such as animal maintenance services, biostatistical management, instrumentation, and other centralized activities required by a large productive scientific organization. An important provision has been the financial support necessary to develop new programs. The core support has been crucial in helping to assure stability and give a degree of flexibility not available to the Institute from University or State funds.